Electrochemical recycling of lithium from lithium-based materials

Abstract

A method for extracting lithium from lithium-based materials to be recycled using an electrochemical reactor includes applying a voltage to a current collector at least partially disposed in an electrolyte carried by the electrochemical reactor, where the lithium-based materials including lithium to be recovered is disposed in the electrolyte and lithium ions move from the lithium-based material towards the current collector upon application of the voltage. In certain variations, the method may also include, prior to the application of the voltage, applying a current to the current collector.

What is claimed is: 
     
         1 . A method for extracting lithium from lithium-based materials to be recycled using an electrochemical reactor, the method comprising:
 applying a voltage to a current collector at least partially disposed in an electrolyte carried by the electrochemical reactor, wherein the lithium-based materials comprising lithium to be recovered is disposed in the electrolyte and lithium ions move from the lithium-based material towards the current collector upon application of the voltage.   
     
     
         2 . The method of  claim 1 , wherein the voltage is a steady voltage greater than or equal to about 1 mV versus Li/Li +  to less than or equal to about 50 mV versus Li/Li + . 
     
     
         3 . The method of  claim 1 , wherein the lithium ions form a lithium film on one or more surfaces of the current collector. 
     
     
         4 . The method of  claim 3 , wherein the lithium film has a thickness greater than or equal to about 1 micrometer to less than or equal to about 20 micrometers. 
     
     
         5 . The method of  claim 3 , wherein the voltage is applied until a preselected thickness of the lithium film is achieved. 
     
     
         6 . The method of  claim 5 , wherein the voltage is applied for a period greater than or equal to about 30 seconds to less than or equal to about 5 minutes. 
     
     
         7 . The method of  claim 1 , wherein the method further comprises, prior to the application of the voltage, applying a current to the current collector. 
     
     
         8 . The method of  claim 7 , wherein the current is a steady current greater than or equal to about 0.01 mA/cm 2  to less than or equal to about 0.1 mA/cm 2 . 
     
     
         9 . The method of  claim 7 , wherein the current is applied for a predetermined time period greater than or equal to about 30 seconds to less than or equal to about 5 minutes. 
     
     
         10 . The method of  claim 7 , wherein the current is applied until a cell voltage reaches about 50 mV Li/Li + . 
     
     
         11 . The method of  claim 7 , wherein the voltage is applied until a cell current decays to a near zero value within about 5% of the current. 
     
     
         12 . The method of  claim 1 , wherein the electrolyte is an electrolyte suspension comprising the lithium-based materials, and the electrolyte suspension is prepared by contacting the electrolyte and the lithium-based materials. 
     
     
         13 . The method of  claim 1 , wherein the current collector is a first current collector, and the electrochemical reactor further comprises a second current collector, and the lithium-based material is coated on one or more surfaces of the second current collector. 
     
     
         14 . A method for extracting lithium from lithium-based materials to be recycled using an electrochemical reactor, the method comprising:
 applying a voltage between a first current collector and a second current collector each at least partially disposed in an electrolyte in the electrochemical reactor, wherein the lithium-based materials comprising lithium to be recovered is disposed in the electrolyte and lithium ions move from the lithium-based material and plate onto the second current collector upon application of the voltage to form a lithium film.   
     
     
         15 . The method of claim  15 , wherein the voltage is a steady voltage greater than or equal to about 1 mV versus Li/Li +  to less than or equal to about 50 mV versus Li/Li +  and the voltage is applied until a preselected thickness of the lithium film is achieved. 
     
     
         16 . The method of  claim 15 , wherein the method further comprises, prior to the application of the voltage, applying a steady current greater than or equal to about 0.01 mA/cm 2  to less than or equal to about 0.1 mA/cm 2  between the first current collector and the second current collector. 
     
     
         17 . The method of  claim 16 , wherein the current is applied until a cell voltage reaches about 50 mV Li/Li + . 
     
     
         18 . The method of  claim 15 , wherein the electrolyte is an electrolyte suspension comprising the lithium-based materials, and the electrolyte suspension is prepared by contacting the electrolyte and the lithium-based materials. 
     
     
         19 . The method of  claim 15 , wherein lithium-based material is coated on one or more surfaces of the second current collector. 
     
     
         20 . A method for extracting lithium from lithium-based materials to be recycled using an electrochemical reactor, the method comprising:
 applying a current greater than or equal to about 0.01 mA/cm 2  to less than or equal to about 0.1 mA/cm 2  between a first current collector and a second current collector each at least partially disposed in an electrolyte in the electrochemical reactor, wherein the lithium-based materials comprising lithium to be recovered is also disposed in the electrolyte; and   when a cell voltage reaches about 50 mV Li/Li + , applying a voltage greater than or equal to about 1 mV versus Li/Li +  to less than or equal to about 50 mV versus Li/Li +  between the first current collector and the second current collector, wherein lithium ions move from the lithium-based material and plate onto the second current collector upon application of the voltage to form a lithium film, and wherein the voltage is applied until the lithium film has a thickness greater than or equal to about 1 micrometer to less than or equal to about 20 micrometers.